Thin-Walled Tube for Dispensing Apparatus

Abstract

A dip tube for a dispensing apparatus, in particular an pump spray assembly for dispensing a liquid fragrance such as perfume or cologne. The dip tube is an extruded thin-walled polymer dip tube configured to provide substantial invisibility when disposed in a liquid fragrance product. In contrast to the prior art that aims to match the refractive index of the dip tube polymer and perfume, the present invention enables use of polymers that having a substantially different refractive index than that of the liquid fragrance, and instead provide a thin-walled tube that is rendered substantially invisible in the liquid fragrance. In one embodiment, the difference in refractive index is 0.04 or more, and in one embodiment is in a range of 0.045 to 0.20. This is the opposite approach taken in the prior art, which relied on refractive index matching, and substantially zero difference.

1 . A dip tube configured to provide substantial invisibility when disposed in a liquid fragrance in a glass container, comprising:
 a non-fluoropolymer extruded thin-walled polymer dip tube having a substantially different refractive index than that of the liquid fragrance, wherein the difference in refractive index is 0.04 or more,   and wherein the wall thickness of the dip tube is no greater than 6 mils (0.152 mm) to render the thin-walled polymer dip tube substantially invisible in the liquid fragrance in the glass container.   
     
     
         2 . The dip tube of  claim 1 , wherein the difference in refractive index is in a range of 0.045 to 0.20 
     
     
         3 . The dip tube of  claim 2 , wherein the wall thickness of the dip tube is in a range of 2 mils (0.051 mm) to 5 mils (0.127 mm). 
     
     
         4 . The dip tube of  claim 3 , wherein the outer diameter of the dip tube is in a range of 1.5 mm to 2.5 mm. 
     
     
         5 . The dip tube of  claim 4 , wherein the difference in refractive index is compared to a liquid fragrance having a refractive index in a range of 1.38 to 1.41. 
     
     
         6 . The dip tube of  claim 5 , wherein the extruded polymer has refractive index in a range of 1.45 to 1.48. 
     
     
         7 . The dip tube of  claim 2 , wherein the extruded polymer comprises at least 90 percent by weight of polymethylpentene (PMP). 
     
     
         8 . The dip tube of  claim 1 , wherein the extruded polymer comprises polymethylpentene (PMP) having a refractive index in a range of 1.45 to 1.48, the wall thickness of the dip tube is in a range of 2 mils (0.051 mm) to 5 mils (0.127 mm), and the outer diameter of the dip tube is in a range of 1.5 to 2.5 mm. 
     
     
         9 . The dip tube on claim  10 , wherein the extruded polymer comprises at least 95 percent by weight of polymethylpentene (PMP). 
     
     
         10 . The dip tube of  claim 9 , wherein the extruded polymer comprises polymethylpentene (PMP) having a flexural modulus of greater than 29,000 psi. 
     
     
         11 . The dip tube of  claim 9 , wherein the extruded polymer comprises polymethylpentene (PMP) having a light transmittance of greater than 92%. 
     
     
         12 . The dip tube of  claim 1 , wherein the extruded polymer comprises cyclic olefin copolymer having a refractive index in a range of 1.52-1.56, the wall thickness of the dip tube is in a range of 2 mils (0.051 mm) to 5 mils (0.127 mm), and the outer diameter of the dip tube is in a range of 1.5 to 2.5 mm. 
     
     
         13 . The dip tube of  claim 1 , the extruded polymer comprises cyclic olefin copolymer having a refractive index in a range of 1.52-1.56, the wall thickness of the dip tube is in a range of 2 mils (0.051 mm) to 5 mils (0.127 mm), and the outer diameter of the dip tube is in a range of 1.5 to 2.5 mm. 
     
     
         14 . A dispensing apparatus for dispensing an spray of a liquid fragrance from a glass container holding the liquid fragrance via a manual pump assembly connected to the container, the pump assembly including a dip tube having a distal end that extends into the liquid fragrance and a proximal end connected to a nozzle spray and pump for dispensing the spray of liquid fragrance, wherein the dip tube comprises:
 an extruded polymer thin-walled dip tube configured to provide substantial invisibility when disposed in a liquid fragrance in a glass container.   the extruded polymer dip tube comprising a non-fluoropolymer having a substantially different refractive index than that of the liquid fragrance, wherein the difference in refractive index is 0.04 or more,   and wherein the wall thickness of the extruded polymer dip tube is no greater than 6 mils (0.152 mm) to render the thin-walled dip tube substantially invisible in the liquid fragrance in the glass container.   
     
     
         15 . The dispensing apparatus of  claim 14 , wherein the difference in refractive index is compared to a liquid fragrance having a refractive index in a range of 1.38 to 1.41. 
     
     
         16 . The dispensing apparatus of  claim 15 , wherein the extruded polymer comprises at least 90 percent by weight of polymethylpentene (PMP) having a refractive index in a range of 1.45 to 1.48, the wall thickness of the dip tube is in a range of 2 mils (0.051 mm) to 5 mils (0.127 mm), and the outer diameter of the dip tube is in a range of 1.5 to 2.5 mm. 17 The dispensing apparatus of claim  16 , wherein the extruded polymer comprises polymethylpentene (PMP) having a flexural modulus of greater than 29,000 psi and a light transmittance of greater than 92%. 
     
     
         18 . The dispensing apparatus of claim  17 , wherein the extruded polymer comprises at least 95 percent by weight of polymethylpentene (PMP). 
     
     
         19 . The dispensing apparatus of  claim 18 ,l wherein the dip tube is substantially invisible when disposed in the liquid fragrance in a glass container configured to hold 1 to 8 fluid ounces of the liquid fragrance, and the refractive index of the glass is in a range of 1.5 to 1.6. 
     
     
         20 . The dispensing apparatus of  claim 15 , wherein the dip tube is substantially invisible when disposed in the liquid fragrance in a glass container configured to hold 1 to 8 fluid ounces of the liquid fragrance, and the refractive index of the glass is in a range of 1.5 to 1.6.